Sulfonating coal-tar dyes.



UNITED STATES PATENT OFFICE EDWARD D. KENDALL, OI ELIZABETH, NEW JERSEY, ASSIGN B OF ONE-HALF '10 LOUIt.

n1. HAGGIN, OF CLUSTER, NEW JERSEY, AND MARGARET V. HAGGIN- AN D ALLANMoCULLOI-I, OF NEW YORK, N. Y., AND H. ESK MULLER, OF MONTCLAIR, NEWJERSEY, EXEGUTORS OF JAMES B. HAGGIN. DECEASED,

SULEONATING cost-rm DYES.

1,217,462. fio nrawlng.

' Toall whom it may concern:

Be it known that I, Enwano D. KENDALL, a citizen ofthe United States,residing at. Elizabeth, in the county of Union and State of New Jersey,have invented a new and useful Process for Sulfonating Goal-Tar Dyes, ofwhich the following is a specification.

The usual methods of preparing sulfoacid dyes (dyes containing the SO,Hgroup) require the use of expensive filming sulfuric acid, or the stillmore costly sulfuric anhydrid and the manufactural operationsnecessitate the use of specially adapted plants and require skilled andsupervised labor and the objects of my invention are to avoid the use ofexpensive agents and provide a simple process by which the dyer himselfmay easily and cheaply preare his sulfo-acid dyes from the suitableEasie colorific bodies or compounds thereof.

In carrying out my invention I first repare or purchase acid alkalimetalsul ate, preferably, for cheapness, hydrogen sodium sulfate, commonlyknown as bisulfate of soda (NaI'ISOJ and convert this into sodiumdisulfate (Na S O.,) by application of heat (using say an ordinaryporcelain evaporating dish on a sand-bath) until the temperature offusion is reached and for a sufficient time to vaporize the water soformed and freed: when the fluid sodium disulfate thus produced becomesquiescent, after the passing off of the aqueous vapor, I removetemporarily the source of heat and when the temperature has fallensomewhat I add to the disulfate monohydrated sulfuric acid (H 80 in theproportion of one chemical equivalent and then renew the application ofheat while stirring the contents of the porcelain vessel with a heavyglass rod; the persulfated body thus produeed may be represented by theformula NILES2()7.II2S()4; it solidifies when cooling and may be keptfor an indefinite time in air-tight iron receptacles, even cans of thinsheet iron, but the dyer, at any time, may easily and quickly preparethis acid-agent when required for use and roeeed as follows to obtainthe sulfo-aei dye desired:

after preparing the persulfated sodium body and continuing the moderateheat required to keep this acid-agent fluid, he

Specification of Letters Patent.

Application filed July 13, 1916i Serial No. 109,040.

should add gradually and stir intosay seven ounces of it one ounce ofthe dye-stufi' tobe sulfonatcd (which may be, for example, one of theti'iphcnylinethane group of coal-tar dyes say commercial rosaniliiihydrochlorid) after having pulverized or granulated the same andthoroughly dried it by sub ecting it, in the open air, for a suffic enttime to a temperature f about 110? 3.; the stirring should be cbntinueduntil the said dye-stuff shall have been thoroughly incorporated withthe sulfonating acid-agent and for ten or fifteenminutes lou er; thenallowing the mass to cool, prefera 1y with continual stirring, whichyields the mixture in granular or fiaginental form, the dyer may at onceuse it for dyeing wool or silk by dissolving it in hot water, theacid-condition of the bath so formed being necessary in dyeing wool orsilk and the presence of the sodium salt in the bath being not only nodetriment thereto but precisely what is required to retard the too rapidabsorption of the dye by theiavidity of the wool or silk for the same,whereby the first portions of the wool 01' silk put into the bath may betoo quickly or excessively dyed at the expense of the portions whifiifollow.

Should the dyer wish to keep hafirl a supply of the said sulfonatingacid-agent it should, of course, be kept from contact with the air andfor this purpose glass-stbp cred bottles or'jars may be conveniently useShould it be desired to separate the sulfonated dye-stufi' from excessof sulfuric acidin the sulfonating mixture, as would be advisable inpreparing the dye for market, this may be done, by the dye-manufacturer,by, dissolving in water the entire product of the herein describedprocess of sulfonation and stirring into the solution an equivalentamount of lime or barium ear-.- bonate; allowing the heavy sulfate soformed to settle, filtering the liquid and evaporating the filtrate todryness. I claim:

1. The herein described process of sulfonating coal-tar dyes, whichconsistsin converting hydrogen sodium sulfate into sodiumdisulfate andthen ersulfatinastthis as; a

with one chemical equiva ent of ggnonohy drated sulfuric acid and thenadding to this persulfated body, when in estate of fusion,

the pulverized and dehydrated e'oul-tar dye to be suli'onuted, withthorough admixture until sulfonution of the dye is etfected,substantially as herein described.

2. The herein described process of sulfonating coal-tar dyes, whichconsists in perslllfuting an alkali-metal disulfnte by incorporatingtluerewith one chemical equivalent of monohydruted sulfuric acid andadding to this persulfatul body, when in a state of fusion, thepulverized :uld dehydrated eoal-turdye to he sulfonuted, sul stantinllyas herein described.

8. The herein described process of snlfonuting coal-tar dyes, whichconsists in persnlfuting an alkali-metal disulfute by incorporatingtherewith one chemical equivalent of llltfll0ll \'tll'tlt0(l sulfuricacidfland adding to this persulfatcd body, when in at State of fusion,the pulverized and dehydrated eoul-tur dye to he Hulfonuted, after--wnr(l (llhSOlVlllg the entire llnlss Ill 'uter and removing excess ofsulfuric acid with an equivalent amount of calcium hydroxid; thenfiltering the solution and evaporating the filtrate to dryness,substantially usherein described;

EDWARD l). KENDALL.

